在MySQL中,LIMIT子句与SELECT语句一起使用,以限制结果集中的行数。LIMIT子句接受一个或两个offset和count的参数。这两个参数的值都可以是零或正整数。 
offset:用于指定要返回的第一行的偏移量。 Count:用于指定要返回的最大行数。 Limit子句接受一个或两个参数,当指定两个参数时,第一个参数是偏移量,第二个参数表示计数,而当只指定一个参数时,它表示从结果集开始返回的行数。 LIMIT语法: SELECT column1, column2, ...
FROM table_name
LIMIT offset, count; 如下表“Data”,其中包含三列“Firstname”、“Lastname”和“Age”。 
要从“Data”表中检索前三行,我们将使用以下查询: SELECT * FROM Data LIMIT 3; 要从“Data”表中检索第2-3行(包括),我们将使用以下查询: SELECT * FROM Data LIMIT 1, 2; 下面是PHP mysql实现查询的代码示例: 示例1:Limit条件 <?php
$link = mysqli_connect("localhost", "root", "", "Mydb");
if ($link == = false) {
die("ERROR: Could not connect. ".mysqli_connect_error());
}
$sql = "SELECT * FROM Data LIMIT 2";
if ($res = mysqli_query($link, $sql)) {
if (mysqli_num_rows($res) > 0) {
echo "<table>";
echo "<tr>";
echo "<th>Firstname</th>";
echo "<th>Lastname</th>";
echo "<th>Age</th>";
echo "</tr>";
while ($row = mysqli_fetch_array($res)) {
echo "<tr>";
echo "<td>".$row['Firstname']."</td>";
echo "<td>".$row['Lastname']."</td>";
echo "<td>".$row['Age']."</td>";
echo "</tr>";
}
echo "</table>";
mysqli_free_result($res);
}
else {
echo "No matching records are found.";
}
}
else {
echo "ERROR: Could not able to execute $sql. ".mysqli_error($link);
}
mysqli_close($link); 输出: 
注:“res”变量存储函数mysql_query()返回的数据。 每次调用mysqli_fetch_array()时,它都会从res()集中返回下一行。 while循环用于遍历表“data”的所有行。 示例2:使用面向对象方法的Limit子句 <?php
$mysqli = new mysqli("localhost", "root", "", "Mydb");
if ($mysqli == = false) {
die("ERROR: Could not connect. ".$mysqli->connect_error);
}
$sql = "SELECT * FROM Data LIMIT 2";
if ($res = $mysqli->query($sql)) {
if ($res->num_rows > 0) {
echo "<table>";
echo "<tr>";
echo "<th>Firstname</th>";
echo "<th>Lastname</th>";
echo "<th>Age</th>";
echo "</tr>";
while ($row = $res->fetch_array()) {
echo "<tr>";
echo "<td>".$row['Firstname']."</td>";
echo "<td>".$row['Lastname']."</td>";
echo "<td>".$row['Age']."</td>";
echo "</tr>";
}
echo "</table>";
$res->free();
}
else {
echo "No matching records are found.";
}
}
else {
echo "ERROR: Could not able to execute $sql. ".$mysqli->error;
}
$mysqli->close(); 输出:

示例3:使用PDO方法的Limit子句 <?php
try {
$pdo = new PDO("mysql:host=localhost;dbname=Mydb", "root", "");
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}
catch (PDOException $e) {
die("ERROR: Could not connect. ".$e->getMessage());
}
try {
$sql = "SELECT * FROM Data LIMIT 2";
$res = $pdo->query($sql);
if ($res->rowCount() > 0) {
echo "<table>";
echo "<tr>";
echo "<th>Firstname</th>";
echo "<th>Lastname</th>";
echo "<th>Age</th>";
echo "</tr>";
while ($row = $res->fetch()) {
echo "<tr>";
echo "<td>".$row['Firstname']."</td>";
echo "<td>".$row['Lastname']."</td>";
echo "<td>".$row['Age']."</td>";
echo "</tr>";
}
echo "</table>";
unset($res);
}
else {
echo "No matching records are found.";
}
}
catch (PDOException $e) {
die("ERROR: Could not able to execute $sql. ".$e->getMessage());
}
unset($pdo); 输出:

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